摘要:

Zirconium dioxide (ZrO2) films have been grown on Si(100) and Si(111) substrates at 800 °C by vacuum evaporation. A channeling spectrum of the Rutherford backscattering on the ZrO2films shows that ZrO2films [tetragonal (200)] are epitaxially grown on Si(100) substrate at 800 °C, which is consistent with x‐ray diffraction and reflection high‐energy electron diffraction observations. The spread of crystallite orientation in the epitaxial film is estimated to be 0.32°, by analyzing the angular dependence of the total backscattering yield.

ISSN:0021-8979    

DOI:10.1063/1.340093

出版商:AIP    

年代:1988

数据来源: AIP

摘要:

Experimental results are reported on the transport of a relativistic electron beam by image charge effects. The transport system consisted of a cylindrical metal tube periodically interrupted by transverse conducting grids with high transparency. Partial cancellation of the beam electric fields increased the space‐charge‐limited current level, allowing propagation in a magnetically self‐pinched mode. A 400‐keV, 4‐kA beam traveled 30 cm in high vacuum through 10 focusing foils. Capture of the beam was almost 100% efficient; beam emittance was not severely degraded during capture and transport. The radius of the self‐contained beam was 1.4 cm; the beam position was centered by the image current in the transport tube to within 1 mm. The favorable results imply that image charge focusing could be considered for transport in high‐current linear induction accelerators.

ISSN:0021-8979    

DOI:10.1063/1.340094

出版商:AIP    

年代:1988

数据来源: AIP

摘要:

The effect of electron irradiation in alkali glasses is studied. A quantitative model is described in which the scattering and the energy loss of the primary electrons are investigated. The theory of multiple collisions is derived in a mathematically simple way, permitting the calculation of the potential inside the irradiated volume. Our analysis enables us to explain the alkali migration reported by several authors.

ISSN:0021-8979    

DOI:10.1063/1.340095

出版商:AIP    

年代:1988

数据来源: AIP

摘要:

We report preliminary results on the low‐threshold operation of interrupted‐growth GaAs/(Al,Ga)As step‐index separate‐confinement heterostructure lasers grown on misoriented substrates by molecular‐beam epitaxy. Growth was performed simultaneously on (100) substrates misoriented 1° and 6°, respectively, towards the nearest (111)Aface. The 6° orientation exhibited the better morphology and lowest threshold current density (260 A cm−2for a cavity length of 607 &mgr;m). The 1° orientation yielded the higher slope efficiency (0.43 W/A for a single facet). The growth was twice interrupted for 3 min each time for Al effusion cell temperature adjustment between the growth of the inner and outer cladding layers.

ISSN:0021-8979    

DOI:10.1063/1.340096

出版商:AIP    

年代:1988

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.341186

出版商:AIP    

年代:1988

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.340097

出版商:AIP    

年代:1988

数据来源: AIP